This invention relates to a method for manufacturing cooling devices. More particularly, this method relates to a method for manufacturing cooling devices that are made from metal shaped section part elements.
Methods for manufacturing cooling devices are known in the art. For example, WO 97/27619 discloses a method for manufacturing several shaped metal elements forming a cooling device which is incorporated herein by reference. This cooling device is mounted onto semi-conductor components. The section part elements have a plurality of grooves and bead strips that fit into them. The section part elements are fitted into each other by applying pressure in a transverse direction.
In addition, these shaped metal elements are formed as extruded sections. The outward protruding groove walls of these shaped section elements or the bead strips are pushed inwards into the corresponding grooves of the neighboring shaped-section part elements, bending inwards and deforming plastically so that each bead strip entering its associated groove is physically locked in place.
The connection for these shaped elements only works if the wall strengths of the bead strips and grooves plugged into each other are sufficiently great. Thus, it is necessary to have high compressive forces for the deformation of these bead strips. In addition these connection points between the bead strips and the grooves are not liquid proof, so that these cooling devices can only be used if gaseous cooling agents are led through.
To overcome this problem the present invention sets forth a method for manufacturing a cooling device that has a liquid proof connection of the shaped section part elements which results in a sufficiently stable connection with a minimum required wall strength of the connecting sections.
The invention relates to a method for manufacturing a cooling device made from shaped section part elements that has a liquid proof connection which results in a sufficiently stable connection. This method results in a minimum required wall strength for these connecting sections. This method is at least partially achieved by laying wires of high-purity aluminum in the corresponding grooves and subsequently molding these wires together with the bead strips that are to be pressed in the connecting sections. These wires are plastically deformed and fill the remaining gaps.
The plastically deformed wire adheres to the surface of the shaped section by means of cold welding and this process leads to an adhering and sealed connection. This results in a high-quality, liquid-proof connection of the shaped section part elements in a longitudinal direction. Thus the result is that the whole shaped-section element component becomes much more stable.
Because this method uses soft wire there is a reduction in the pressure needed for plastic deformation. Thus, there are fewer relatively high forming forces needed which are caused by an edge rolling die. In addition, the shaped section elements that support the deformation forces can be more easily built. In addition to saving weight, this results in a better transmission of heat.
Highly pure (99.9% purity) annealed aluminum wire should be used with this method. These wires can have a diameter of 1-1.5 mm and can be molded into the connection gaps that are formed without having the material emerge on the outside.
Overall, the intimate connections between the shaped elements have better heat transmission values in the area of these connection points. In addition as stated earlier, another benefit is that the high compression forces needed to form this cooling device can be reduced.